Monckeberg's arteriosclerosis is a clinically benign form of calcification of the blood vessels. Needless anxiety results from failure to differentiate this condition from intimal arteriosclerosis. Intimal arteriosclerosis often goes on to progressive occlusion of the blood vessels and carries an unfavorable prognosis. In Monckeberg's arteriosclerosis, thrombosis of the blood vessels in the extremities does not occur, and in patients who have been observed for many years there has been no tendency to develop impaired circulation. The favorable prognosis in Monckeberg's arteriosclerosis has been pointed out by Moschcowitz.1The clinical characteristics that distinguish Monckeberg's arteriosclerosis from other forms are extreme calcification of the arteries of the lower extremities in young and middle-aged persons who have no symptoms or signs of impaired circulation. Calcification of the blood vessels is usually discovered by accident when a roentgenogram is made for arthritis, fracture, or some other bone or joint condition. There are no